THE IMAGINARY HANCiK AND THOUGH. 



49 



Actually, on any reasonable hypothesis of support by flotation 

 the differences would probably lie somewhere between these two 

 extremes, but nearer the lower than the higher value. 



It has been pointed out that an hypothesis of support by flo- 

 tation not only allows, but has a necessary consequence, of the 

 likelihood that compensation would not be complete within the limits 

 of the range, but might be partly distributed over the crust on either 

 side. This want of balance may take place in two ways, and the 

 one which will be considered first is a superelevation of a part of 

 the range, accompanied by a bending down of the crust on either 

 side. In table No. 10 the result of such a departure from cora- 



Table 10. — Corrections to the deflections due to the hypothesis of 

 support by simple flotation, on two separate suppositions of partial 

 support, corrected by depression of the adjoining tracts, supposed 

 to be confined (A) to the topography and (B) to the compensation. 





Deflections resulting peom Hypothesis 



T)ist-a ii cp from 















l 'l ■ l 'l IM I 1 1 'Mil 



southern edge of 



XT 



I. 











superelevated tract 



JSo. 





No. 



11 





(in miles). 

















(A) 





(B) 



(A) 





(B) 



50 N. 





















40 



— 2 





— 1 



— 4 





— 1 



30 



— 4 





2 



— / 





— !> 



20 



— 7 





— 3 



— 12 





— 5 



10 



— 12 





— 4 



— 20 





— 7 







— 27 





— 5 



— 44 





— 8 



10 



— 11 





— 4 



— 19 





— 8 



20 



— 5 





— 3 



— 12 





— 7 



30 



2 





— 2 



— 8 





— 6 



40 



1) 





— 1 



— 5 





— 4 



60 



+ 1 









— 3 





— 3 



60 



+ 2 









— 1 





— 2 



70 



+ 3 





+ 1 









— 1 



80 



+ 4 





+ 1 



+ 1 









90 



+ 4 





+ 1 



+ 2 





+ 1 



lOO^S. 



+ 4 





+ 2 



+ 3 





+ 1 



plete local support by flotation is given on two separate supposi' 

 tions, namely (1) that a tract 100 miles in width is superelevated 

 by 1,500 ft. and that the defect in support is taken up by a depres- 

 sion of the crust on either side, gradually diminishing to nothing 

 in 100 miles ; and (2) that the same tract is superelevated by 3,000 ft. 



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